Two step process for refining of lubricating oils with aluminum chloride



' 2,872,413 Two STEP PROCESS FOR REFINING oF LUBRICATING M. ELLIOTT Erm.l

Feb. 3,v 1959 OILS WITH ALUMIHUMCHLORIDE .Filed Oct. 5, 1956 PNN hun QPR Q ED N un tmb umwum, .N MAQ TWO STEP PROCESS FR REFINING F LUBRI- CATING DELS WITH ALUMINUM CHLRIDE Marshall Elliott and Leslie U. Franklin, Port Arthur, Tex., assignors to GullY Oil Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Application October 5, 1956, Serial No. 614,305

7 Claims. (Cl. 20S-297) This invention relates to a process and more particularly to a process of manufacturing high quality lubricating oils with the aid of anhydrous aluminum chloride.

Anhydrous aluminum chloride has been known and used for some years ras a refining agent for the production of lubricating oils characterized by low carbon residue test. The chloride is an expensive reagent, the techniques of using it are more involved and more costly than conventional refining processes, and its use is therefore ordinarily reserved for the production of extraquality, premium-priced products. Its refining effect is accompanied by a substantial loss to sludge and also by the destruction of the lubricating qualities of a substantial portion of the stock undergoing treatment. For those reasons minimization of the percentage of stock so deteriorated in effecting the desired refining is a primary object in the use of this reagent.

Prior use of anhydrous aluminum chloride in relining of petroleum has been largely at temperatures of the order of from 500 F. to 300 F. The stock undergoing treatment has been agitated with a reagent usually for periods of several hours. Soon after the hydrocarbon lubricating stock and reagent are brought together, the anhydrous aluminum chloride forms a complex or sludge with a portion of the oil and from that point on the complex, for all practical purposes, is the treating agent. This complex however is not an unchanging material: at the time of its initial formation it is a relatively free flowing uid but gradually during its reaction with hydrocarbon material it becomes increasingly less fluid and will finally become solid if kept in contact with hydrocarbons at a reaction temperature. Long Contact of the complex with aluminum chloride at the high temperatures of the prior art has resulted in destroying the lubricating qualities of a substantial portion of the stock, often as high as ten percent, Shortening the time of contact has resulted in inadequately refined lubricants, as shown for instance by undesirably high residue test.

We have found that by' the two-stage treating process which is the subject of this invention we can treat the lubricant for relatively short periods of time at relatively low temperatures and still produce a highly refined oil. Though we have been working regularly in this eld for many years we are surprised by the results obtained by this method. The improved results obtained by this method are not due to divergence in one or two respects from conventional methods of using aluminum chloride but by the combination of a continuous process involving two treating stages, the short time of treatment in each stage, the two specified temperature ranges during treatment, use of partially spent complex from the second treating stage as treating agent in the iirst treating stage, the use of fresh aluminum chloride as the initial treatment agent iu the second treating stage, and the specified high degree of agitation of lubricating stock and treating agent.

The lubricating stock to be treated is in all cases a Well dried material, as any moisture would destroy the anhydrous aluminum chloride. The first-stage treatment is performed with 'a high degree of agitation for a period of approximately four to ten minutes and at a temperature within the approximate range of 185 F. to 215 F. The treating agent used in this rst treating stage will be susequently described. Lubricating stock and treating agent are discharged from the iirst treating step, the treating agent is settled out of the treated lubricating stock, and the lubricating stock is then subjected to a second treating stage after having lirst been brought within the approximate 'temperature range of 140 F. to F. The second treating stage is continued for a period of approximately four to ten minutes at the temperature just mentioned, and fresh anhydrous aluminum chloride is introduced at this point as the reagent therein. As previously stated, the aluminum chloride within a short period forms a complex with a portion of the lubricating stock and this complex from there on serves as the reagent. The proportion of anhydrous' aluminum chloride to lubricating stock in the second treating stage should be not substantially less than four percent by weight, based on the weight of the stock treated. In fact, on the balance of all factors, four percent is a very advantageous proportion and this proportion of aluminum chloride will'ordinarily combine with approximately live or six percent of the lubricating stock in forming the complex. At the conclusion of the prescribed treating period for the'second treating stage the treated stock and the aluminum chloride complex are transterredto a settling chamber for separation, and the so separated and partially expended reagent from the second stage is then used as the reagent in the rst treating stage. l

The accompanying Table I shows the results obtained with use of various percentages of anhydrous aluminum chloride. Y

Table I Carbon Percent Gas Oil Percent Aluminum Chloride Residue Reduction Content of Used of` Product in Carbon Treated Residue Oil 0.29 23. 7 (l) 0. 13 6l. 8 3. 9 0. 14 63. 2 4. 0 0. 13 67. 5 5. 8 0. 14 G5. 9 (1) '1 Not determined.

In contacting the lubricating stock and treating agent it is important that the agitation of the two be at a suiciently high rate to maintain all the stock and all the treating agent at all times in violent motion. For our purpose, this will be best accomplished by limiting the size of the contacting chamber to dimensions which assure that the entire contents thereof will be completely turned over at least ten times per minute. Accomplishment of this degree of agitation has been found to require the expenditure of power at a rate of not less than three horsepower per barrel of lubricating stock charged per minute. With the rae of turnover much below ten times per minute, the stock and the treating agent may both be kept in continuous motion, but nevertheless the degree of contact between treating agent and lubricating stock may be vary low due to the fact that they may be largely separated andbe circulating in parallel streams. As in all reacting of non-miscible liquids, a high degree of shear is required in order to attain intimate contact.

A ow diagram of our process accompanies this specification and the process will be described with reference thereto. Referring to the diagram:

The lubricating stock to be treated is charged to the system through line 1, and is passed through a heating coil 2 in heater 3. From that point it passes through line 4 to first stage contactor 5. Thence the once treated stock is conducted through conduit 6 to settler 7. Sludge settling from the treated stock in settler 7 is removed therefrom through conduit 8. Settled once-treated lubricating stock leaves settler 7 through conduit 9 and is forced by pump 10 through heat exchanger 11 to second stage contactor 12. A stream of cooling water enters heat exchanger 11 through conduit 13 and is conducted therefrom through conduit 14. Fresh anhydrous aluminum chloride is fed through feeder 15 to second stage contactor 12, and the twice treated lubricating stock from contactor 12, together with accompanying complex, is conducted through line 16 to settler 17 with the aid of pump 18. Settled fully treated lubricating stock is conducted from settler 17 and out of the system through conduit 19, and the complex of aluminum chloride and lubricating stock is removed from the base of settler 17 through conduit 20. This complex is then forced by pump 21 through line 22 back into mixer 5 to constitute the treating agent in the first treating stage. Of course, settler 17 may be positioned immediately above first stage mixer and the complex is then permitted to drain by gravity into mixer 5.

In the conduct of our process a dry lubricating oil stock to be treated with aluminum chloride is continuous* ly charged through conduit 1 to a heating coil 2 in a heat transfer device 3, and it is there heated to a temperature suicient to permit its introduction through conduit 4 into contactor 5 at a temperature within the approximate range of 180 F. to 215 F. In contactor 5 the heated incoming oil is subjected to extremely high turbulence mixing with, and treatment by, a partially expended complex of anhydrous aluminum chloride and oil from a subsequent part of the system which will be later described. The lubricating stock and the complex with which it has been treated in contactor 5 both leave that vessel through conduit 6 and are conducted to a settler 7` Settler 7, which may advantageously have a cone bottom, is of much larger dimension than contactor 5, to permit relatively quiescent settling of the expended complex from the treated oil. The settled spent complex, commonly called sludge at this stage, is withdrawn from the bottom lof settler 7 and is discharged from the system through conduit 8. Settled oil is withdrawn from the top of settler 7 through conduit 9 and this material is forced by pump 10 to and through a heat exchanger 11. A cooling uid is introduced into heat exchanger 11 through conduit 13 and removed therefrom through conduit 14. The flow of oil and the cooling fluid through heat exchanger 11 are proportioned to deliver the settled oil into second stage contactor 12. at a temperature within the approximate range of 140 F. to 165 F.

The oil which has been given a first stage treatment with partially expended complex in contactor 5 at a temperature of approximately 180 F. to 215 F. is given a second stage treatment in contactor 12 at 150 F. with fresh anhydrous aluminum chloride. An extremely high. degree of mixing is maintained in contactor 12 as previously mentioned, and fresh aluminum chloride introduced thereinto from feeder 15 promptly forms a complex witha portion of the oil, the complex in turn serving as a treating agent. Both in contactor 5 and in contactor 12, the residence time of the lubricating stock is of the order of from four to ten minutes.

The treated lubricating stock and the aluminum chloride complex with which it has been reacted leave contactor 12 through conduit 16 and this material is pumped.

iii

by pump 18 into settler 17. As in the case of settler 7, the dimensions 4of settler 17 are chosen to permit a relatively quiescent state of the materials therein, conducive to good settling of the aluminum chloride complex from the lubricating stock, and the residence time of lubricating stock in the settler may well be of the order of from four hours to twenty-four hours. The actual time of settling in settlers 7 and 17 will be such as will effect substantially complete settling of complex from treated stock and this may vary from stock to stock.

The proportion of aluminum chloride to lubricating stock is chosen to obtain the desired degree of relining of the lubricating stock, and under most conditions a pro portion of four percent by weight of anhydrous aluminum chioride to lubricating stock is effective as shown in Tahie i. Proportions of about this order of magnitude have a further advantage in that this amount of aluminum chloride is substantially completely expended by the time it has served as treating agent in the second and lirst stages of treatment,

Settled treated lubricating stock from settler 17 is conducted away from the system through conduit 19 for inishing, and any tine particles of complex which may remain suspended in the oil withdrawn from settler ffl' may be removed by percolation through a bed of fullers earth or by the process commonly known as clay contacting. The stock is then heated to distill off the low boiling products of reaction between aluminum chloride and lubricating stock, and additional material is then distilled oil to obtain a residue of the desired high viscosity for the finished oil.

The purpose of this process is to produce highly refined lubricating oil of premium quality from high grade, high value, lubricating stocks. This it accomplishes in a degree substantially higher than is .attainable by the practices of the prior art. The degree of improvement is well shown in Table 1I, herewith. This table has three columns of comparable data and the figures in each column are the average of three closely comparable runs. Column 1 gives data on the process described and claimed herein. Columns 2 and 3 each give data on the process of the prior art.

T able II Run Number 1 2 3 Tests of Untreated Lubricating Stock:

Gravity, API 28. 4 28. 4 28. Ll Viscosity, SUV- at F 456 467 L175 at 210 F-.. 63. 7 64. 4 64. 7 Viscosity Index. 108 108 108 Carbon Residue 0. 38 0. 35 0. 3l Treatment of Lubricating Stock:

Number of Stages 2 l l Minutes per Stage... l0 240 240 Temperature,

First Stage. 200 275 275 Second Stage.. Aluminum Chloride Used, Percent.. 4.0 4. 0 4. 0 Finished Oil:

Yield, Percent 48. 3 4.16 44. 2 Gravity, API 27. 6 27.8 27. 6 Viscosity', SUV- at 100 F- 1,162 1,100 1,181 at; 210 F 99. 9 99.6 101.0 Viscosity Index. 102 102 102 Carbon Residue 0.33 0.25 0.30

Tables lil, IV, and V, respectively, show the supporting data which has been averaged and presented in columns 1, 2, and 3 of Table Il. Reference to these tables showsl a high degree of comparability of the runs and results averaged in the various columns of Table II, and it will he noted that the three 'separate runs shown in each of Tables IH, IV, and V closely confirm the results obtained in the other runs of the same table.

Referring to the tests of untreated lubricating stock in all the runs of Tables lll, IV, and V, -it will be noted that substantially identical lubricating stock was used in all runs and that a uniform four percent of anhydrous aluminum chloride was used in all runs.

asraais" Table IH Run Number 1 2 3 Average Tests o Untreated Lubricating Stock:

Gravity, API 28. 3 28. 4 28. 4 Viscosity, SUV- t 100 F 460 456 64.7 68. 7 111 108 Carbon Residue 0. 37 0.38 Treatment of Lubricating Stock:

Number of Stages 2 2 2 2 Minutes per Stage l 10 10 l0 Temperature, F-

First Stage 200 200 200 200 Second Stage 150 150 150 150 Aluminum Chl Percent 4 0 4.0 4 0 4.0 Finished Oil:

Yield, Percent 48. 1 48.1 48. 8 48. 3 Gravity, API 27. 9 27. 7 27. 2 27. 6 Viscosity, SUV- at 100 F 1,136 1,119 1, 231 1,162 at 210 F 98.2 98.2 103. 3 99. 9 Viscosity Index.. 101 102 102 102 Carbon Residue 0.29 0. 31 0. 38 0. 33

Table I V Run Number 1 2 3 Average Tests of Untreated Lubricating Stock:

Gravity, API 28. 3 28. 4 28. 4 28. 4 Viscosity, SUV- at 100 F 473 467 460 467 at 210 F 64. 1 64. 3 64. 7 64. 4 Viscosity Index 106 108 111 108 Carbon Residue. 0.38 0. 29 0. 37 0.35 Treatment of Lubrcatin Number of Stages 1 1 1 1 Minutes per Stag 240 A 240 240 240 Temperature, F. 275 275 275 275 Aluminum Chloride Uscd,

Percent 4. 0 4.0 4.0 4. 0 Finished Oil:

Yield, Percent 45. 5 45. 6 45. e 45.0 Gravity, API 28. 1 27. 8 27. 6 27.8 Viscosity, SUV- at 100 F 1,077 1, 043 1,360 1,160 at 210 I" 95. 6 94. 0 109.3 99. 6 Viscosity Index 102 102 102 102 Carbon Residue 0. 23 0.21 0. 30 0.25

Table V Run Number 1 2 3 Average Tests of Untreated Lubricating Stock:

Gravity, API 28. 4 28. 5 28. 2 28. 4 Viscosity, SUV- at 100 F 481 414 580 475 67. 5 60, 5 66. 2 64. 7 115 106 102 108 0.30 0.25 0. 38 0.31

1 1 1 1 p M0 240 240 240 Temperature, F 275 275 275 275 Aluminum Chloride Used,

Percent 4. 0 4. 0 4. 0 4. 0 Finished Oil:

Yield, Percent 44. 4 41. 2 47. 0 44. 2 Gravity, API 27. 8 27. 5 27. 5 27.6 Viscosity, SUV- at 100 F 1,196 1,188 1,159 1,181 at 210 F 102. 0 101. 0 99. 5 101.0 Viscosity Index. 102 102 101 102 Carbon Residue 0. 0.27 0. 33 0.30

Table 1H is a tabulation of all values on three separate and closely comparable runs, using the process described and claimed herein, with a ten minute first-stage treatment at 200 F. and a ten minute second-stage treatment at 150 F. It will be noted that the yields of reduced treated oil are in all instances very close, varying only from 48.1% to 48.8%, and that the viscosity of those reduced treated oils varied only from 1119 to 1231 at 100 F. and from 98.2 to 103.3 at 210 F. This is very close conrmance between the tests, and it will subsequently be pointed out that the average yield of these runs is very substantially above the yield of runs made in conformity with the prior art.

Table 1V is a tabulation of all values on three separate and closely comparable runs, using the process of the prior art with a single stage of treatment for four hours at a temperature of 275 F. It will be noted that the yields of reduced treated oil are all within one tenth of one percent of one another, and that the viscosity of those reduced treated oils varied only from 1043 to 1360 at F. and from 94.0 to 109.3 at 210 F. Those viscosities average 1160 at 100 F. and 99.6 at

210 F., which is practically identical with an average of 1162 at 100 F. and 99.9 at 210 F. for the three runs made according to our new process described and claimed herein.

We now point out that we have presented three com parable and mutually conrmatory runs made by our new process and three comparable and mutually confirmatory runs made by the process of the prior art, that the treated stock has in every instance been reduced to the same desired viscosity, and that the yields by our new process average 48.3% on the original charge as compared to a yield of only 45.6% for the stock processed according to the prior art. The 48.3% yield by our process, when compared to the 45.6% yield by the prior art process, is in the ratio of 106% to 100%. In other words our new process yields 6% more nished oil of the same test than can be obtained by the prior art, and in the production of high value oils this is a vary pronounced improvement.

Table V is, like Table IV, a tabulation of all values on three separate and closely comparable runs, using the process of the prior art with a single stage of treatment for four hours at a temperature of 275 F. While Table IV tabulates a series of runs with identical yield accompanied by very moderate variation in viscosity of the end product, Table V tabulates a similar series varying moderately in yield but having substantially identical viscosity. The three yields vary from 41.2%, through 44.4% to 47.0%. These average 44.2% yield on the original charge as compared to an average yield of 48.3% by our new process. The 48.3% yield by our process, when compared to the 44.2% average yield obtained in the three runs of Table V is in the ratio of 109 to 100. ln other words our new process yielded 9% more iinished oil, of substantially tbc same viscosity, than that obtained in the three prior art process runs tabulated in Table V.

The finishing of the oil to a relatively uniform viscosity in all cases is necessary to show the improvement in yield of lubricating components by our process, but the iinishing of the aluminum chloride treated oil may be varied considerably in industrial practice and the various possible finishing steps do not constitute part of our invention.

We claim:

1. In the refining of a hydrocarbon lubricating oil stock with anhydrous aluminum chloride, the continuous two-stage treating process that comprises: subjecting the lubricating oil stock in dry condition in a first treating stage to intimate contacting for a period within the approximate range of from four to ten minutes and at a temperature within the approximate range of from 180 F. to 215 F. with a complex formed by the reaction of anhydrous aluminum chloride with such lubricating oil stock, the said contacting being of a severity to consume power at the rate of at least three horsepower per barrel of lubricating stock charged per minute and at a rate to completely turn over the stock and complex at least ten times per minute; separatingr the said complex from the so-treated lubricating oil stock and discharging the separated complex from the system; subjecting to so-separated lubricating oil stock in a second treating stage to intimate contacting with fresh anhydrous aluminum chloride for a period within the approx"- mate range of from four to ten minutes at a temperature within the approximate of from F. to

165 F., the said contacting being of a severity to consume power at the rate of at least three horsepower per barrel of lubricating stock charged per minute and at a rate to completely turn over the stock and complex at least ten times per minute, this contacting producing an aluminum-chloride treated lubricating oil stock and a complex of anhydrous aluminum chloride and lubricating oil stock; separating the said aluminum-chloride treated lubricating oil stock from the aluminum-chloride complex; distilling from the said aluminum-chloride treated lubricating oil stock any lower-'boiling and lov er viscosity components resulting from the action of aluminum chloride on said stock; and using the separated aluminum chloride complex from the second treating stage as thc treating complex in the rst treating stage.

2. in the refining of a hydrocarbon lubricating oil stock with anhydrous aluminum chloride, the continuous two-stage treating process that comprises: subjecting the lubricating oil stock in dry condition in a first treating stage to intimate contacting for a period within the approximate range of from four to ten minutes and at a temperature within the approximate range of from 180 F. to 215 F. With a complex formed by the reaction of anhydrous aluminum chloride with such lubricating oil stock, the said contacting being of a severity to consume power at the rate of at least three horsepower per barrel of lubricating stock charged per minute and at a rate to completely turn over the stock and complex at least ten times per minute; separating the said complex from the so-treated lubricating oil stock and discharging the separated complex from the system; subjecting the so-separated lubricating oil stock in a second treating stage to intimate contacting with fresh anhydrous aluminum chloride for a period withinV the approximate range of from four to ten minutes at a temperature within the approximate range of from 140 F. to 165 F, the said contacting being of a severity to consume power at the rate of at least three horsepower per barrel of lubricating stock charged per minute and at a rate to completely turn over the stock and complex at least ten times per minute, this contacting producing an aluminumchloride treated lubricating oil stock and a complex of anhydrous aluminum chloride and lubricating oil stock; separating the said aluminum-chloride treated lubricating oil stock from the aluminum-chloride complex; and using the separated aluminum chloride complex from the second treating stage as the treating complex in the first treating stage.

3. In the refining of a hydrocarbon lubricating oil stock with anhydrous aluminum chloride, the continuous two-stage treating process that comprises: subjecting the lubricating oil stock in dry condition in a rst treating stage to intimate contacting for a period within the approximate range of from four to ten minutes and at a temperature within the approximate range of from 180 F. to 215 F. with a complex formed by the reaction of anhydrous aluminum chloride with such lubricating oil stock, the said contacting being at a rate to completely turn over the stock and complex at least ten times per minute; separating the said complex from the so-treated lubricatin y oil stock and discharging the separated complex from the system; subjecting the so-separated lubricating oil stock in a second treating stage to intimate contacting with fresh anhydrous aluminum chloride for a period within the approximate range of from four to ten minutes at a temperature within the approximate range of from 140 F. to 165 F., the said contacting being at a rate to completely turn over the stock and complex at least ten times per minute, this contacting producing an aluminum-chloride treated lubricating oil stock and a complex of anhydrous aluminum chloride and lubricating oil stock; separating the said aluminumchloride treated lubricating oil stock from the aluminumchloride complex; distilling from the said aluminumchloride treated lubricating oil stock any lower-boiling and lower viscosity components resulting from the action of aluminum chloride on said stock; and using the separated aluminum chloride complex from the second treating stage as the treating complex in the first treating stage. v

4. In the refining of a hydrocarbon lubricating oil stock with anhydrous aluminum chloride, thecontinuous two-stage treating process that comprises: subjecting the lubricating oil stock in dry condition in a first treating stage to violent agitation for a period within the approximate range of from four to ten minutes and at a temperature within the approximate range of from 180 F. to 215 F. with a complex formed by the reaction of anhydrous aluminum chloride with such lubricating oil stock; separating the said complex from the so-treated lubricating oil stock and discharging the separated cornplex from the system; subjecting the so-separated lubricating oil stock in a second treating stage to violent agitation with fresh anhydrous aluminum chloride for a period within the approximate range of from four to ten minutes at a temperature within the approximate range of from F. to 165 F., this contacting producing an aluminum-chloride treated lubricating oil stock and a complex of anhydrous aluminum chloride and lubricating oil stock; separating the said aluminum-chloride treated lubricating oil stock from the aluminum-chloride complex; distilling from the said aluminum-chloride treated lubricating oil stock any lower-boiling and lower viscosity components resulting from the action of aluminum chloride on said stock; and using the separated aluminum chloride complex from the second treating stage as the treating complex in the first treating stage.

5. In the refining of a hydrocarbon lubricating oil stock with anhydrous aluminum chloride, the continuous two-stage treating process that comprises: subjecting the lubricating oil stock in dry condition in a first treating stage to intimate contacting for a period within the approximate range of from four to ten minutes and at a temperature within approximately twenty degrees of 200 F. with a complex formed by the reaction of anhydrous aluminum chloride with such lubricating oil stock, the said contacting being of a severity to consume power at the rate of at least three horsepower per barrel of lubrieating stock charged per minute and at a rate to completely turn over the stock and complex at least ten times per minute; separating the said complex from the so-treated lubricating oil stock and discharging the separated complex from the system; subjecting the so-separated lubricating oil stock in a second treating stage to intimate contacting with fresh anhydrous aluminum chloride for a period within the approximate range of from four to ten minutes at a temperature Within a range of approximately forty to fifty Fahrenheit degrees lower than that used in the rst treating stage, the said contacting being of a severity to consume power at the rate of at least three horsepower per barrel of lubricating stock charged per minute and at a rate to completelyl turn over the stock and complex at least ten times per minute, this contacting producing an aluminum-chloride treated lubricating oil stock and a complex of anhydrous aluminum chlo-ride and lubricating oil stock; separating the said aluminum-chloride treated lubricating oil stock from the aluminum-chloride complex; distilling from the said aluminum-chloride treated lubricating oil stoel: any lower-boiling and lower viscosity components resulting from the action of aluminum chloride on said stock; and using the separated aluminum chloride complex from the second treating stage as the treating complex in the rst treating stage.

6. In the reiining of a hydrocarbon lubricating oil stock with anhydrous aluminum chloride, the continuous two-stage treating process that comprises: subjecting the lubricating oil stock in dry condition in a iirst treating stage to intimate contacting for a period within the approximate range of from four to ten minutes and at a vasm/41s temperature within the approximate range of from 180 F to 2l5 F. with a complex formed by the reaction of anhydrous aluminum chlaride with such lubricating oil stock, the said contacting being of a severity to assure continuous intimate contact of all of the complex with all of the lubricating stock; separating the said complex from the so-treated lubricating oil stock and discharging the separated complex from the system; subjecting the so-separated lubricating oil stock in a second treating stage to intimate contacting with fresh anhydrous aluminum chloride for a period Within the approximate range from four to ten minutes at a temperature Within the approximate range of from 140 F. to 165 F., the said contacting being of a severity to assure continuous intimate contact of all of the complex with al1 of the lubricating stock; separating the said aluminum-chloride treated lubricating oil stock from the aluminum-chloride complex; distilling from the said aluminum-chloride treated lubricating oil stock any lower-boiling and lower viscosity components resulting from the action of aluminum chloride onsaid stock; and using the separated aluminum chloride complex from the second treating stage as the treating complex in the first treating stage.

7. In the refining of a hydrocarbon lubricating oil stock with anhydrous aluminum chloride, the continuous two-stage treating process that comprises: subjecting the lubricating oil stock in dry conditi-on in a iirst treating stage to intimate contacting for a period Within the approximate range of from four to ten minutes and at a temperature within the approximate range of from 180 F. to 215 F. with a complex formed by the reaction of anhydrous aluminum chloride with such lubricating oil stock, the said contacting being of a severity to consume power at the rate of at least three horepower per barrel of lubricating stock charged per minute and at a rate to completely turn over the stock and complex at least ten times per minute; separating the said complex from the so-treated lubricating oil stock and discharging the separated complex from the system; subjecting the so-separated lubricating oil stock in a second treating stage to intimate contacting with not substantially less than four percent by weight of fresh anhydrous aluminum chloride for a period within the approximate range of from four to ten minutes at a temperature within the approximate range of from F. to 165 F., the said contacting being of a severity to consume power at the rate of at least three horepower per barrel of lubricating stock charged per minute and at a rate to completely turn over the stock and complex at least ten times per minute, this contacting producing an aluminum-chloride treated lubricating oil stock and a complex of anhydrous aluminum chloride and lubricating oil stock; separating the said aluminum-chloride treated lubricating oil stock from the aluminum-chloride complex; distilling from the said aluminum-chloride treated lubricating oil stock any lower-boiling and lower viscosity components resulting from the action of aluminum chloride o-n said stock; and using the separated aluminum chloride complex from the second treating stage as the treating complex in the first treating stage.

Chittick Iuly 28, 1936 Rippeteau Dec. 3, 1946 

1. IN THE REFINING OF A HYDROCARBON LUBRICATING OIL STOCK WITH ANHYDROUS ALUMINUM CHLORIDE, THE CONTINUOUS TWO-STAGE TREATING PROCESS THAT COMPRISES; SUBJECTING THE LUBRICATING OIL STOCK IN DRY CONDITION IN A FIRST TREATING STAGE TO INTIMATE CONTACTING FOR A PERIOD WITHIN THE APPROXIMATE RANGE OF FROM FOUR TO TEN MINUTES AND 180* F. TO 215* F. WITH A COMPLEX FORMED BY THE REACTION OF ANHYDROUS ALUMINUM CHLORIDE WITH SUCH LUBRICATING OIL STOCK, THE SAID CONTACTING BEING OF A SEVERITY TO CONSUME POWER AT THR RATE OF AT LEAST THREE HORSEPOWER PER BARREL OF LUBRICATING STOCK CHARGED PER MINUTE; AND AT A RATE TO COMPLETELY TURN OVER THE STOCK AND COMPLEX AT LEAST TEN TIMES PER MINUTE* SEPARATING THE SAID COMPLEX FROM THE SO TREATED LUBRICATING OIL STOCK AND DISCHARGING THE SEPARATED COMPLEX FROM THE SYSTEM SUB JECTING TO SO-SEPARATED LUBRICATING OIL STOCK IN A SECOND TREATING STAGE TO INTIMATE CONTACTING WITH FRESH ANHYDROUS ALUMINUM CHLORIDE FOR A PERIOD WITHIN THE APPROXIMATE RANGE OF FROM FOUR TO TEN MINUTES AT A TEMPERATURE WITHIN THE APPROXIMATE RANGE OF FROM 140* F. TO 165* F., THE SAID CONTACTING BEING OF A SEVERITY TO CONSUME POWER AT THE RATE OF AT LEAST THREE HORSEPOWER PER BARREL OF LUBRICATING STOCK CHARGED PER MINUTE AND AT A RATE TO COMPLETELY TURN OVER THE STOCK AND COMPLEX AT ALUMINUM-CHLORIDE TREATED LUBRICATING OIL STOCK AND A COMPLEX OF ANHYDROUS ALUMINUM CHLORIDE AND LUBRICATTING OIL STOCK; SEPARATING THE SAID ALUMINUM-CHLORIDE TREATED LUBRICATING OIL STOCK FROM THE AL COMPLEX; DISTILLING FROM THE SAID ALUMINUM-CHLORIDE TREATED LUBRICATING OIL STOCK ANY LOWER-BOILING AND LOWER VISCOSITY COMPONENTS RESULTING FROM THE ACTION OF ALUMINUM CHLORIDE ON SAID STOCK; AND USING THE SEPARATED ALUMINUM CHLORIDE COMPLEX FROM THE SECOND TREATING STAGE AS THE TREATING COMPLEX IN THE FIRST TREATING STAGE 